The House Energy and Commerce Committee on Monday accused the Biden administration of potentially breaking the law by not properly reappointing former White House medical adviser Anthony Fauci and other top officials within the National Institutes of Health.

But the Department of Health and Human Services vigorously rejected the accusations, calling them political and inaccurate.

The allegations mark an escalation in lawmakers’ attacks on Fauci — who retired from his role as director of the National Institute of Allergy and Infectious Diseases at the end of last year — and the NIH in the wake of the COVID-19 pandemic and the fight over whether risky research helped create the virus. The allegations also call into question around $25 billion in medical research grants awarded by the agency in the past 18 months.

Chair Cathy McMorris Rodgers, R-Wash., has been especially critical of the agency’s research protocols amid questions about NIH’s ongoing funding of EcoHealth Alliance and its subcontracts with the Wuhan Institute of Virology.

In December 2016, the medical research law known as the 21st Century Cures Act established five-year terms for NIH directors, including Fauci as director of the NIAID. Many of those terms were up in December 2021.

But HHS Secretary Xavier Becerra didn’t reappoint them until June 2023, Rodgers and other Energy and Commerce leaders alleged in a July 7 letter. Additionally, the reappointments didn’t include Fauci and former Fogarty International Center Director Roger Glass, who both recently resigned. Fauci now teaches at Georgetown University.

“If Dr. Fauci was never reappointed,” the lawmakers wrote, “every action he took is potentially invalid.”

The committee also released letters and documents about the appointments provided by HHS.

But HHS said the appointments were properly done through the NIH director, and were only retroactively ratified by Becerra in June to guard against bad faith legal challenges amid the committees’ inquiries. An HHS spokesperson said the department stands by the legitimacy of the appointments, noting that the committee ignored five other directors appointed through the same process under Trump.

“The Committee’s allegations are clearly politically motivated and lack merit,” the spokesperson said in a statement.